At Edge, Steven Pinker recently spoke about his forthcoming book, The Better Angels of Our Nature: Why Violence Has Declined. He argues that over long stretches of time, all forms of violence have been persistently decreasing, so that “we may be living in the most peaceful time in our species’ existence.” Pinker supports this claim with lots of historical data, such as homicide rates, per-capita war deaths, declining use of judicial torture, etc. Regarding the death penalty, for instance:

In 18th century England there were 222 capital offenses on the books, including poaching, counterfeiting, robbing a rabbit warren, being in the company of gypsies, and “strong evidence of malice in a child seven to 14 years of age.” By 1861 the number of capital crimes was down to four.

Similarly, in the United States in the 17th and 18th centuries, the death penalty was prescribed and used for theft, sodomy, bestiality, adultery, witchcraft, concealing birth, slave revolt, counterfeiting, and horse theft.

Many of the reforms that led to the abolishing of previously accepted forms of violence (witch hunting, dueling, religious persecution, slavery) can be traced back to the 18th century. What caused this “humanitarian revolution?” Pinker credits the spread of printing and literacy:

Why should literacy matter? A number of the causes are summed up by the term “Enlightenment.” For one thing, knowledge replaced superstition and ignorance: beliefs such as that Jews poisoned wells, heretics go to hell, witches cause crop failures, children are possessed, and Africans are brutish. As Voltaire said, “Those who can make you believe absurdities can make you commit atrocities.”

Also, literacy gives rise to cosmopolitanism. It is plausible that the reading of history, journalism, and fiction puts people into the habit of inhabiting other peoples’ minds, which could increase empathy and therefore make cruelty less appealing.

But wait a minute: weren’t the genocides of the 20th century unprecedented in human history?

Historians who have tried to track genocide over the centuries are unanimous that the notion that the 20th was “a century of genocide” is a myth. Frank Chalk and Kurt Jonassohn, in their The History and Sociology of Genocide, write on page one, “Genocide has been practiced in all regions of the world and during all periods in history.”

What did change during the 20th century was that for the first time people started to care about genocide. It’s the century in which the word “genocide” was coined and in which, for the first time, genocide was considered a bad thing, something to be denied instead of boasted about…

To give some examples: if Old Testament history were taken literally, there were genocides on almost every page; the Amalakites, Amarites, Canaanites, Hivites, Hitites, Jevasites, Midianites, Parazites and many other. Also, genocides were committed by the Athenians in Melos; by the Romans in Carthage; and during the Mongol invasions, the Crusades, the European wars of religion, and the colonization of the Americas, Africa and Australia.

The 65 years since the end of the Second World War have been extraordinarily peaceful by historical standards: no wars between superpowers, no wars between Western European countries, no wars between developed countries at all. There has also been a continuous reduction in systemic violence against vulnerable populations such as racial minorities, women, children, homosexuals, and animals.

Has human nature changed? Probably not. Pinker suggests that while some aspects of human nature encourage violence, there are other aspects that discourage it — and historical forces have increasingly favored the latter. These historical developments include the rise of state justice systems, trade, the “expanding circle” of empathy caused by cosmopolitanism, and:

I think the final and perhaps the most profound pacifying force is an “escalator of reason.” As literacy, education, and the intensity of public discourse increase, people are encouraged to think more abstractly and more universally, and that will inevitably push in the direction of a reduction of violence. People will be tempted to rise above their parochial vantage point, making it harder to privilege their own interests over others. Reason leads to the replacement of a morality based on tribalism, authority and puritanism with a morality based on fairness and universal rules. And it encourages people to recognize the futility of cycles of violence, and to see violence as a problem to be solved rather than as a contest to be won.

Of course, there is no guarantee that historical trends will continue. But one implication of Pinker’s thesis is that, in order for us to reduce violence further, we need to understand what we have been doing right — because “we have been doing something right.” Finally,

the decline of violence has implications for our assessment of modernity: the centuries-long erosion of family, tribe, tradition and religion by the forces of individualism, cosmopolitanism, reason and science.

Now, everyone acknowledges that modernity has given us longer and healthier lives, less ignorance and superstition, and richer experiences. But there is a widespread romantic movement which questions the price. Is it really worth it to have a few years of better health if the price is muggings, terrorism, holocausts, world wars, gulags, and nuclear weapons?

I argue that despite impressions, the long-term trend, though certainly halting and incomplete, is that violence of all kinds is decreasing. This calls for a rehabilitation of a concept of modernity and progress, and for a sense of gratitude for the institutions of civilization and enlightenment that have made it possible.